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Multiorgan dysfunction (MOD) is a consistent feature of the postasphyxial newborn infant. MOD is related to the diving reflex which, when activated by asphyxia, shunts blood from the skin and splanchnic region to the heart, adrenal glands, and brain. The presumed goal is to protect these vital organs from hypoxic-ischemic injury. This study examined patterns of involvement of major organ/systems and combinations of these in infants with postasphyxial hypoxic-ischemic encephalopathy (HIE), and associations between dysfunction and the long-term outcome. Outcome data were available for 130 infants who met 1 or more of 4 eligibility criteria: 1) a 5-minute Apgar score below 5, metabolic acidosis, and/or a lack of respiration for 5 minutes or longer; 2) a need for mechanical ventilation at birth; 3) evidence of encephalopathy (altered consciousness and/or seizures); and/or 4) complete functional assessment of the kidneys, cardiovascular system, lungs, and liver. Severe adverse outcomes (death from postasphyxial HIE, severe cerebral palsy diagnosed in the first year of life, mild or moderate cerebral palsy with blindness or deafness in the first year; moderate cerebral palsy with developmental delay at 21-24 months of age) were noted for 80 of 130 infants, 62% of the total. All infants had at least one organ dysfunction in addition to HIE. The incidence of renal, cardiovascular, pulmonary, and hepatic dysfunction ranged from 58% to 88% of infants having a good outcome and from 64% to 86% of those with an adverse outcome. Pulmonary and hepatic dysfunctions were most frequent. The rate of adverse outcomes increased from 1 to 3 as the number of additional organs involved increased from 1 to 3, but decreased when an additional 4 organs were involved. MOD was universally present in these infants with severe postasphyxial HIE, but was not associated with long-term outcomes.

High-frequency oscillatory ventilation (HFOV) was used to treat 41 infants with persistent pulmonary hypertension of the newborn (PPHN). Of the 37 patients who showed early improvement on HFOV, three died. The remaining 34 patients demonstrated, within one hour of the switchover to HFOV, a rise in mean arterial/alveolar oxygen tension ratio (PaO2/PaO2) from 0.093 +/- 0.041 (SD) to 0.132 +/- 0.051 (p less than .001), and a fall in mean PaCO2 from 42 +/- 10 to 34 +/- torr 9 (p less than .01). Mean airway pressure (Paw) fell significantly (p less than .01) within 12 h. The mean duration of conventional mechanical ventilation before starting HFOV was longer in 13 patients who developed bronchopulmonary dysplasia (BPD) than in 21 non-BPD patients (44.7 +/- 32.3 vs. 19.1 +/- 15.6 h, p less than .002), as was the duration of exposure to Paw greater than 15 cm H2O during that treatment mode (31.8 +/- 21.3 vs. 9.5 +/- 6.0 h, p less than .001). HFOV is often effective in the treatment of patients with PPHN, and early initiation of this type of mechanical ventilation may be associated with a reduced incidence of BPD.

From January 1983 to September 1984 our neonatal ICU (NICU) treated eight endotracheally intubated infants who had suspected airway obstruction characterized by hypercarbia dissonant with severity of lung disease and difficulty in ventilation with lack of chest movement, both on conventional intermittent mandatory ventilation and high-frequency oscillation. Bronchoscopic removal of necrotic tissue was possible in six infants, two of whom survived. Bronchoscopy showed desquamation of epithelial surfaces, leaving encrusted exudations considered to be characteristic of necrotizing tracheobronchitis (NTB). The four nonsurvivors of bronchoscopy and one of the infants not submitted to bronchoscopy had NTB confirmed at autopsy. NTB was not associated with any specific lung disease, humidifier, or ventilator. The autopsy frequency of NTB during this period was 5 per 160 NICU admissions. A separate chart review of unselected autopsied cases in 1981 and 1982 showed that 12 of 284 neonates admitted to the NICU had NTB. NTB appears to be a rediscovered condition related to endotracheal intubation and mechanical ventilation using high mean airway pressures.

The likelihood of survival to 28 days of life was determined retrospectively for 106 infants weighing less than 801 g at birth. Multiple logistic regression analysis revealed that birth weight and inspired oxygen fraction made an independent contribution to the prediction of survival at 8 h of age (predictive accuracy 76%). At 16 and 24 h of age, body temperature, pH, and the presence of spontaneous breaths were the independent variables predicting survival (predictive accuracy 79%). Of 37 infants with calculated chances of survival of less than 50% at 16 h, 29 died (predictive accuracy 78%). Seven of the remaining eight infants who survived "against the odds" either died later of chronic lung disease or had severe handicapping complications by 3 months of age. These predictions are first approximations and are not intended for use in making decisions about patient management.